远程调试hadoop-yarn需要三步走即可：
1，已debug模式启动hadoop-yarn集群，比如想要eclipse debug跟踪resourcemanager，在hadoop安装目录下找到
$hadoop_home/etc/hadoop/yarn-env.sh文件
添加如下一句话
YARN_RESOURCEMANAGER_OPTS="$YARN_RESOURCEMANAGER_OPTS -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=8111"
注：各个参数含义
-Xdebug 启用调试特性 -Xrunjdwp 启用JDWP实现，包含若干子选项： transport=dt_socket JPDA front-end和back-end之间的传输方法。dt_socket表示使用套接字传输。 address=8111 JVM在8111端口上监听请求，这个设定为一个不冲突的端口即可。 server=y y表示启动的JVM是被调试者。如果为n，则表示启动的JVM是调试器。 suspend=y y表示启动的JVM会暂停等待，直到调试器连接上才继续执行。suspend=n，则JVM不会暂停等待。 或者在$hadoop_home/bin/yarn脚本中的，如下脚本找到"$COMMAND" = "resourcemanager"代码，添加对应的变量也同样可以：
fi
echo $CLASSPATH
exit
elif [ "$COMMAND" = "rmadmin" ] ; then
CLASS='org.apache.hadoop.yarn.client.RMAdmin'
YARN_OPTS="$YARN_OPTS $YARN_CLIENT_OPTS"
elif [ "$COMMAND" = "application" ] ; then
CLASS=org.apache.hadoop.yarn.client.cli.ApplicationCLI
YARN_OPTS="$YARN_OPTS $YARN_CLIENT_OPTS"
elif [ "$COMMAND" = "node" ] ; then
CLASS=org.apache.hadoop.yarn.client.cli.NodeCLI
YARN_OPTS="$YARN_OPTS $YARN_CLIENT_OPTS"
elif [ "$COMMAND" = "resourcemanager" ] ; then
YARN_RESOURCEMANAGER_OPTS="$YARN_RESOURCEMANAGER_OPTS -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=8788"
CLASSPATH=${CLASSPATH}:$YARN_CONF_DIR/rm-config/log4j.properties
CLASS='org.apache.hadoop.yarn.server.resourcemanager.ResourceManager'
YARN_OPTS="$YARN_OPTS $YARN_RESOURCEMANAGER_OPTS"
if [ "$YARN_RESOURCEMANAGER_HEAPSIZE" != "" ]; then
JAVA_HEAP_MAX="-Xmx""$YARN_RESOURCEMANAGER_HEAPSIZE""m"
fi
elif [ "$COMMAND" = "nodemanager" ] ; then
CLASSPATH=${CLASSPATH}:$YARN_CONF_DIR/nm-config/log4j.properties
CLASS='org.apache.hadoop.yarn.server.nodemanager.NodeManager'
YARN_OPTS="$YARN_OPTS -server $YARN_NODEMANAGER_OPTS"
if [ "$YARN_NODEMANAGER_HEAPSIZE" != "" ]; then
JAVA_HEAP_MAX="-Xmx""$YARN_NODEMANAGER_HEAPSIZE""m"
fi
elif [ "$COMMAND" = "proxyserver" ] ; then
CLASS='org.apache.hadoop.yarn.server.webproxy.WebAppProxyServer'
YARN_OPTS="$YARN_OPTS $YARN_PROXYSERVER_OPTS"
if [ "$YARN_PROXYSERVER_HEAPSIZE" != "" ]; then
JAVA_HEAP_MAX="-Xmx""$YARN_PROXYSERVER_HEAPSIZE""m"
fi
elif [ "$COMMAND" = "version" ] ; then
CLASS=org.apache.hadoop.util.VersionInfo
YARN_OPTS="$YARN_OPTS $YARN_CLIENT_OPTS"
elif [ "$COMMAND" = "jar" ] ; then
CLASS=org.apache.hadoop.util.RunJar
YARN_OPTS="$YARN_OPTS $YARN_CLIENT_OPTS"
elif [ "$COMMAND" = "logs" ] ; then
CLASS=org.apache.hadoop.yarn.logaggregation.LogDumper
YARN_OPTS="$YARN_OPTS $YARN_CLIENT_OPTS"
elif [ "$COMMAND" = "daemonlog" ] ; then
CLASS=org.apache.hadoop.log.LogLevel
YARN_OPTS="$YARN_OPTS $YARN_CLIENT_OPTS"
else
CLASS=$COMMAND然后启动或者重启hadoop 集群2，eclipse设置断点，找到hadoop-yarn-server-resourcemanager相应类代码，加入想要调试的代码3，设置debug 远程应用程序找到debug->debug configurations->remote java application《1》给应用起名，随便起《2》填写连接属性：connect properties host: port:填写hadoop集群的监听端口号《3》debug 运行即可 三步完成当有任务提交到集群跑到相应类时，eclipse就会跳到debug对应断点上！